The correct answer is option 1. India exports sugar to other countries because its production is in excess of the demand in the country. This means that India produces more sugar than what is needed domestically, so the surplus is exported to other countries where there is a demand for sugar.

Option 2, stating that India exports sugar because its sugar mills are located near the ports, is not a valid reason. The proximity of sugar mills to ports may aid in the transportation of sugar for export, but it does not determine the reason for exporting sugar.

Option 3, suggesting that India exports sugar because the country needs foreign exchange, is partially correct. While it is true that exporting sugar can help generate foreign exchange, it does not specifically explain why sugar is chosen as an export commodity.

Option 4, stating that India exports sugar because its sugar is superior to that of other countries, is not a valid reason. The quality of Indian sugar compared to other countries may be a factor in the export market, but it does not explain the primary reason for exporting sugar.

In conclusion, India exports sugar because its production exceeds the domestic demand in the country, making it an attractive commodity for export to other countries.